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what is faster: in_array or isset? [closed]
...t-in function.
These can be demonstrated by using an array with values (10,000 in the test below), forcing in_array to do more searching.
isset: 0.009623
in_array: 1.738441
This builds on Jason's benchmark by filling in some random values and occasionally finding a value that exists in the a...
Numpy how to iterate over columns of array?
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– Ibrahim Muhammad
Sep 23 '13 at 17:08
49
For those wondering, array.T isn't costly, as it just c...
Underscore: sortBy() based on multiple attributes
...dArray = _(patients).chain().sortBy(function(patient) {
return patient[0].name;
}).sortBy(function(patient) {
return patient[0].roomNumber;
}).value();
When the second sortBy finds that John and Lisa have the same room number it will keep them in the order it found them, which the first so...
Group by multiple columns in dplyr, using string vector input
...
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
A simple explanation of Naive Bayes Classification
...les, would receive misleadingly high scores.
In general, for an example, 70% of our data can be used as training set cases. Also remember to partition the original set into the training and test sets randomly.
Now I come to your other question about Naive Bayes.
To demonstrate the concept of Naï...
Drawable image on a canvas
...|
edited Dec 15 '18 at 12:07
answered Apr 8 '14 at 8:36
Gá...
How does the algorithm to color the song list in iTunes 11 work? [closed]
...
+50
I approximated the iTunes 11 color algorithm in Mathematica given the album cover as input:
How I did it
Through trial and error...
CGContextDrawImage draws image upside down when passed UIImage.CGImage
...
Instead of
CGContextDrawImage(context, CGRectMake(0, 0, 145, 15), image.CGImage);
Use
[image drawInRect:CGRectMake(0, 0, 145, 15)];
In the middle of your begin/end CGcontext methods.
This will draw the image with the correct orientation into your current image context...
Changing font size and direction of axes text in ggplot2
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301
Use theme():
d <- data.frame(x=gl(10, 1, 10, labels=paste("long text label ", letters[1:10]...
Get number days in a specified month using JavaScript? [duplicate]
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609
// Month here is 1-indexed (January is 1, February is 2, etc). This is
// because we're using 0...